Pyridinium cationic-dimer antimalarials, unlike chloroquine, act selectively between the schizont stage and the ring stage of Plasmodium falciparum
摘要:
Malaria is a leading cause of death in developing countries, and the emergence of strains resistant to the main therapeutic agent, chloroquine, has become a serious problem. We have developed cationic-dimer type antimalarials, MAP-610 and PMAP-H10, which are structurally different from chloroquine. In this study, we introduced several substituents on the terminal phenyl rings of PMAP-H10. The electronic and hydrophobic properties of the substituents were correlated with the antimalarial activity and cytotoxicity of the compounds, respectively. Studies with synchronized cultures of malarial plasmodia showed that our cationic-dimers act selectively between the schizont stage and the ring stage of the parasitic cycle, unlike chloroquine, which has a stage-independent action. Thus, the mechanism of action of our antimalarials appears to be different from that of chloroquine, and our compounds may be effective against chloroquine-resistant strains. (C) 2008 Published by Elsevier Ltd.
Synthesis of Quinolines via Rh(III)-Catalyzed Oxidative Annulation of Pyridines
作者:Guoyong Song、Xue Gong、Xingwei Li
DOI:10.1021/jo201266u
日期:2011.9.16
Selective synthesis of quinolines has been achieved via oxidative annulation of functionalized pyridines with two alkyne molecules under Rh(III)-catalyzed cascade C–H activation of pyridines using Cu(OAc)2 as an oxidant. The selectivity of this reaction is oxidant-dependent, particularly on the anion of the oxidant.
Rhodium(iii)-catalyzed oxidative mono- and di-olefination of isonicotinamides
作者:Xiaohong Wei、Feng Wang、Guoyong Song、Zhengyin Du、Xingwei Li
DOI:10.1039/c2ob25773d
日期:——
[RhCp*Cl2]2 can catalyze the oxidative coupling of secondary isonicotinamides with activated olefins using Cu(OAc)2 as an oxidant. The selectivity can be controlled by the solvent. In MeCN, the mono-olefination and two-fold oxidation reaction is the major pathway, while in THF this reaction gave mostly diolefination products. In both cases, the coupled products contain an exocyclic CC bond.
The elemental sulfur–DMSO couple was found to efficiently promote the oxidativecoupling of active methylhetarenes with amines to yield amides under simple heating conditions. When 2-methylquinoline was used as the methylhetarene component, the formation of the expected 2-quinolinecarboxamides from anilines could be efficiently catalyzed by iron, nickel and cobalt salts. The method displayed good functional